PLS HELP ME FIND THE SURFACE AREA PLS

Abox contains 1 plain pencil and 4 pens. a second box contains 5 color pencils and 5 crayons. one item from each box is chosen at random. what is the probability that a plain pencil from the first box and a color pencil from the second box are selected? write your answer as a fraction in simplest form.

Idont understand math at all! : o( use this scenario to answer the remaining questions: brenton purchased a new bedroom set for $4,500.00. he lives in arizona and pays a 8.75% sales tax. if he made a 50% down payment and financed the rest, what amount did he finance? what is the total sales tax brenton will pay? enter your answer in currency format, round to the nearest cent. what was brenton's total amount financed? enter your answer in currency format, round to the nearest cent.

An arc subtends a central angle measuring 7pi/4 radians what fraction of the circumference is this arc?