Simplify 3^-9/3^-12 answer quickly

Aparking lot is to be 400 feet wide and 370 feet deep. how many standard-sized cars fit in this lot considering a double-loaded (w4) two way traffic set up, an angle of 90° and a sw of 9’ 0’’? (do not consider handicapped parking spaces, and consider 15’ for turning aisles). show your work.

How many of the 250 grandparents in the population would you expect to prefer online shopping with merchant a? merchant a: 4 merchant b: 6 merchant c: 2 merchant d: 3 other: 5 none: 5 answer choices: a.about 4 b.about 8 c.about 40 d.about 21

Anyone? 15m is what percent of 60m; 3m; 30m; 1.5 km?