Please help Calculus

Will mark determine whether the conjecture is true or false. give a counterexample for any false conjecture. given: points r, s, and t conjecture: r, s, and t are coplanar. a) false; the points do not have to be in a straight line. b) true c) false; the points to not have to form right angles. d) false; one point may not be between the other two.

Annabelle's homework is 75% it took her three hours how long should she estimate it will take her to complete her homework.

Sally deposited money into a savings account paying 4% simple interest per year.the first year,she earn $75 in interest.how much interest will she earn during the following year?