A triangle, where the two angles are 30° and 90°, what are the remaining angles

He ! a group of farmers planned to clean 80 acres of wheat per day to finish the work on schedule. right before the work started, they received a new piece of machinery that them clean 10 more acres per day than originally planned. as a result of increased productivity in the last day before the deadline they only had to clean 30 acres. how many acres of wheat did the group of farmers have to clean?

Given that the images represent 4 steps in the construction of a line segment congruent to a given line segment, which is step 3 in the construction?

Ireally don't understand this, i'm really an idiot but i want to know how to figure this out. !