Does anyone take practical math because I have this projects for Saving for Retirement and I am totally lost.

Aball is dropped from a height of 10m above the ground. it bounce to 90% of its previous height on each bounce. what is the approximate height that the ball bounce to the fourth bounce?

The equation line of cd is y=-2x-2. write an equation of a line parallels to line cd in slope-intercept form that contains point (4,5)

Jessa bought a yoyo from a company that claims that, with each retraction, the string rolls up by 60% of the original length. she sets up a tape measure and throws the yoyo 3 times. her data are charted below. throw length of string (feet) 1 3 2 1.8 3 1.08 jessa wants to find the sum of the length of string after 10 throws. what is the sum of the lengths, rounded to the nearest hundredth?