Use logarithmic differentiation to find the derivative of the function. y  =  x^8  sin(x)

Need on this one asap im almost done with this subject

Susie wants to take her friend out for lunch.she wants to spend $9.75 each person. how much will she spend in all.

Sally deposited money into a savings account paying 4% simple interest per year. the first year, she earned $75 in interest. how much interest will she earn during the following year? show your work and explain your reasoning in the space provided below.