idk if I'm right but I'm pretty sure BC is just half of BD which 16 so BC=8?? im sorry I'm not much of a help if I'm unsure... if all else fails then just make an educated guess
It's not clear what "tree numbers" or a "gaff" are.
16
0.2 = 3.2 gotta watch out for the decimals
A negative correlation: when the number of years increase the value of the car decrease.
By determining the length of TV using TV^2=15^2+10^2-2(15)(10)cos80, and then determining the value of x using 15^2=TV^2+10^2-2(TV)(10)cosx.