Simplify (7x + 2 + 8x4) – (2x – 5 – 8x4) + (3x + 5x4)

a. 15x4 + 14x + 7
b. 21x4 + 8x + 7
c. 21x4 + 14x + 7
d. 15x4 + 19x + 7

Haruka hiked several kilometers in the morning. she hiked only 66 kilometers in the afternoon, which was 25% less than she had hiked in the morning. how many kilometers did haruka hike in all?

Nikolas calculated the volume of the prism. his work is shown below.

Ariel is working at a meat packing plant for 5 nights a week. her regular wage is $11 an hour. she earns tine and a half for any overtime hours. this week she worked 9 hours of over time .how much will ariel earn for overtime this week ?