ONLY NUMBER 1 please help

S-7< 3 i need answering this problem someone asap answer

Determine the difference: 3.2 × 1010 – 1.1 × 1010. write your answer in scientific notation.

Jake bakes and sell apple pies. he sells each pie for $5.75 . the materials to make the pies cost $40. the boxes jake puts the pies in cost & 12.50 total. how many pies does jake need to sell to earn a profit of $50