PLS HURRY Which can be used to describe the expression? Check all that apply.

(r ^-4)^3

There are three factors of r^ -4.

The expression is equal to 1 over 12 factors of r.

Adding the exponents will create an equivalent expression.

Multiplying the exponents will create an equivalent expression.

The expression simplifies to 1/r^7

Find the values of y: 3y^3(y^2+ 2/3y)=0

In the given triangle, ∠aed ∼ ∠ abc, ad = 6.9, ae = 7.2, de = 5.2, and bc = 10.2. find the measure of bd and ce. round your answer to the nearest tenth.

Afactory makes propeller drive shafts for ships. a quality assurance engineer at the factory needs to estimate the true mean length of the shafts. she randomly selects four drive shafts made at the factory, measures their lengths, and finds their sample mean to be 1000 mm. the lengths are known to follow a normal distribution whose standard deviation is 2 mm. calculate a 95% confidence interval for the true mean length of the shafts. input your answers for the margin of error, lower bound, and upper bound.