Can you help me with this, it is True or False

What graph correctly matches the equation y equals two negative x

Find the greatest common factor of -30x 4 yz 3 and 75x 4 z 2.

A33 gram sample of a substance that's used to detect explosives has a k-value of 0.1473. n = noekt no = initial mass (at time t = 0) n = mass at time t k = a positive constant that depends on the substance itself and on the units used to measure time t = time, in days