Answer:

Explanation:
In all atoms, the number of protons = number of electrons, as a result the atom is neutral. Losing or gaining electrons will make the atom electrically charged and we call an electrically charged atom an ion.
Ca 2+ would be the symbol because losing two negative electrons makes calcium's nucleus more positive by two protons.
Answer:
|Δf| = 37.3 kHz
Explanation:
given,
peak velocity = 4 m/s
speed of the sound = 1500 m/s
frequency = 7 MHz




= 37.3 kHz
|Δf| = 37.3 kHz
hence, frequency shift between the opening and closing valve is 37.3 kHz
How to gain muscular endurance?<span>Combine strength days with cardio days.Reduce your amount of rest between sets.Do fast-paced, high-intensity lifting.Choose compound movements over isolation.10 Ways to Protect Your Joints >>> Remember: Routine is the enemy.Go for hybrid exercises.<span>Add explosive movements to your workout.</span></span>
I dont see it ;-; REEEEEEEE
The sled experiences friction against the ground