8 packs test the 3. Andre's school orders some new supplies for the chemistry lab. The online store shows a pack of 10 test tubes costs $4 less than a set of nested beakers. In order to fully equip the lab, the school orders 12 sets of beakers and 8 packs of test tubes. a. Write an equation that shows the cost of a pack of test tubes, t, in terms of the cost of a set of beakers, b. 10 t = -4b 100:-4 4 b. The school office receives a bill for the supplies in the amount of $348. Write an equation with t and b that describes this situation. lot 12b Bt-348 c. Since t is in terms of b from the first equation, this expression can be substituted into the second equation where t appears. Write an equation that shows this substitution. d. Solve the equation for b.