Twice the difference between x and k

Aquantity with an initial value of 3900 decays exponentially at a rate of 35% every hour. what is the value of the quantity after 0.5 days, to the nearest hundredth?

When rolling 26 sided number cube what are the chances some of the role will be seven

Aregular hexagonal pyramid has a base area of 45 in2 and a lateral area of 135in 2. what is the surface are are of the regular hexagonal pyramid