A family has two cars. During one particular week, the first car consumed 15 gallons of gas in the second consumed 40 gallons of gas. The two cars drove a combined total of 900 miles, and the sum of their fuel efficiencies was 35 miles per gallon. What were the fuel efficiencies of each of the cars that week? Please help

Zed is making a centerpiece for his dining room table by putting sand in a cube-shaped vase. the vase is 0.25 meters in length, width, and height. he bought 25 kg of sand. assume the density of dry sand is 1,602 kgm3. what is the volume of the sand that zed purchased? the volume of the sand is approximately m3. enter your answer as the number that correctly fills in the blank in the previous sentence. if necessary, round your answer to six decimal places, like so: 42.536475