May one fold laundry on Shabbat?
Regarding regular clothing from the washer/dryer (as opposed to clothing from a dry cleaner/laundromat that have creases, and thus have different Halachot), many poskim permit one to fold laundry if the intention is to just keep the house looking neat and clean. However, if the intention is to lessen the work he has after Shabbat, it would be forbidden as that falls into the category of preparing for weekday as well.
It’s preferable to avoid folding laundry altogether, by placing the laundry in a place which won’t make the house look messy if such an option is available.
When folding, one must make sure not to sort the clothing; meaning if there is a pile of clothing one shouldn’t pick all the socks first and then other clothing, as that would fall under the prohibition of בורר. Rather, he should take whatever comes first and fold that.
I don’t know which beer is Yashan. How should I go about this?
Although the prohibition of Chadash is a Torah prohibition and one should try to buy products which are Yashan, it’s important to know that there are few leniencies with the prohibition of Chadash.
Some permit it because it grew outside the land of Israel.
Others permit it because it grew in a non-Jew’s land while others permit it because there are double doubts ספק-ספיקא) whether the product is from last year and it’s permitted or from this year, and even if it’s from this year, maybe it’s from before Pesach and is permitted.
Even though each of those rulings were rejected by most of the poskim and also by the Shulchan Aruch, but when putting all those leniencies together, many are lenient. For example, most products we buy today grow outside the land of Israel and it didn’t grow on Jewish field. Furthermore, its status is not known if it Yashan or not.
Many poskim feel one can be even more lenient when it comes to drinking beer and other liquid products for the reasons above, and also because of the opinion of the Lecham Mishne who wrote that beer is permitted since generally, we don’t view whatever comes out of the fruit as the actual fruits; therefore, whatever is withdrawn from the malted grain (most use barley) is not forbidden. The P’nei Yehoshua agreed that outside the land of Israel one can be lenient with this.
When buying a product made from one of the five grains, is one required to determine its Yashan status by calling the manufacturer or a Rabbi, or to purchase one of the booklets which list the common products?
There is a machloket Rishonim whenever we have a leniency of sfek-sfeka, if one is still required to find out if the item is indeed kosher, or if he can permit it without searching. The Rashba holds if possible, one must find out, and only if it’s not possible to find out may he permit it. Whereas the Mahari held it’s permitted even without any investigation. The Rema sided with the lenient opinion and the Shach forbade.
Chacham Ovadia held one doesn’t need to find out, especially in a case where only some of the doubts will be resolved, but it’s not possible to find out all doubts.
 אור לציון ח״ב עמוד רז וכן שמירת שבת כהלכתה פרק טו הלכה מט בשם משנה ברורה סי’ שב ס״ק יח
 לרי״ף, רא״ש והרמב״ם הוי דאורייתא אולם לרבינו ברוך ואור זרוע הוא דרבנן. ובה״ג וריב״א התירו לגמרי
 תוספות אסרו
 רמ״א סימן רצג ס״ג
 סוף מס’ תרומות
 קונטרס אחרון קידושין אות נא
 פרק אלו טרפות דף נג ע״ד
 מהרא״י ס״ס מז
 ר״ע איגר יו״ד סי״ח