228 88Ra ^{228}_{\ 88}{\rm Ra} then decays through a series of beta-minus decays; eventually, another isotope of thorium,

228 90Th ^{228}_{\ 90}{\rm Th} , is formed. How many beta-minus decays will occur during this chain process?

Acharge of 8.4x10^-4 c moves at an angle of 35 degrees to a magnetic field that has a field strength of 6.7x10^-3 t. if the magnetic force is 3.5 x10 ^-2 n, how fast is the charge moving?

Aplane travels 1000 miles in 5 hours .what is the planes average speed?

Because air contracts as it cools, the air pressure inside a freezer is typically lower than on the outside. why do ice cubes inside a freezer tend to shrink over time? a. the ice dissolves oxygen from the air, forming a denser crystalline matrix.b. the ice reacts chemically with carbon dioxide in the air, forming gaseous carbon compounds.c. the ice melts, and then the liquid freezes as ice crystals on the bottom of the freezer.d. the ice sublimes, and then the water vapor deposits as ice crystals on the sides of the freezer.