Small beads of iridium-192 are sealed in a plastic tube and inserted through a needle into breast tumors. if an ir-192 sample has an initial activity of 560 dpm, how much time is required for the activity to drop to 35 dpm (t1/2 = 74 days)?

What is the relationship between wind and ocean waves? question 17 options: wind moving at higher speeds will transfer more energy to the water, resulting in stronger waves. wind moving at higher speeds will transfer energy over a larger part of the ocean water, resulting in waves with a shorter wavelength. winds moving at higher speeds with cause water to move forward at faster rates, causing larger ocean waves. winds moving at higher speeds will affect deeper water, resulting in waves that move at a faster rate. how do temperature and salinity affect deepwater currents? question 15 options: as temperatures and salinity levels of water increase, the water rises to the surface where it creates currents as it moves to colder regions. they create changes in wind direction, moving denser water in the same direction as the wind and causing the deepwater circulation patterns found in the ocean. they equalize the forces on undersea currents caused by the coriolis effect as they replace more dense water with less dense water. they create density differences that cause dense deepwater currents to flow toward the equator where they displace less dense, warmer water above them.

Which statement describes the phase change that occurs when dry ice is placed in an open container at room temperature?

If you burn 46.6 g of hydrogen and produce 416 g of water, how much oxygen reacted