42141x10^4 do u guys know the answer

What is the percentage by mass of silicon (si) in iron aluminum silicate (fe3al2(sio4)3)?

An alcohol thermometer makes use of alcohol's changing in order to measure temperature. as the temperature goes up, the alcohol contained in the thermometer increases in volume, filling more of the thermometer's tube.

Suppose the universe were completely empty except for one object-a solid sphere moving through space of 100 km/s. what sort of path would the object be moving in? explain your answer