. A sample of Strontium-90 has a Half-Life of 28.1 years. How long will it take for a sample to decay to 12.5% of its original mass?
A sample of Ge-66 (Half-Life = 2.5 hours) sat for 10 hours and only 5 grams remain. What wog
the mass of the original sample?
w
Element X is a Radioisotope. If a 100-kg sample of Element X decays to 12.5 kg in 1 day, what
is the Half-Life of Element X in hours?
Strontium-90 (Half Life = 28.1 years) is used as a Radioactive Tracer in Medical and Agricultural
Studies. How many atoms out of a 1.68 x 1023 atom sample will remain undecayed after 56.2
years?
What percentage of a 900-gram sample of Potassium-37 (Half-Life = 1.23 seconds) exists after
6.15 seconds?

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.

8. what happens to matter during a chemical reaction

Which is a characteristic of the electron sea model for metallic bonding? molecular orbitals overlap to produce bands. electrons flow easily between metal nuclei. electrons are in fixed positions in the orbitals. atomic nuclei are arranged in an irregular pattern.