Dont use me for points on this! If there is a 7.5 gram apple on one side of a scale, what mass would you need to balance the scale? Question 14 options:

2 grams, 2 grams, 2 grams

3 grams, 2 grams, and .5 grams

4 grams, 1 gram, and 1 gram

5 grams, 2 grams, and 0.5 grams

5 grams, 2 grams, 0.5 grams

Explanation:

One side of the scale has a 7.5-gram weight. To balance the scale, the other side needs to have a 7.5-gram weight as well.

Among all the options given, only the last option adds up to 7.5 grams.

I hope this helps!

5.283x10^28

Explanation:

Each photon emits an energy of hf, where f is the frequency and h being planck's constant.

The heat required to raise the temperature of water from 20°C to 100°C is

Q = mS(dT)

= (density of water)(volume of water)(4200J/K)(80K)

= (10^3 kg/m^3)(0.25x10^-3 m^3)(4200J)(80)

= 84000J

Energy of each photon having wavelength 12.5x10^-2 m is

(6.62x10^-34)((3x10^8)/(12.5x10^-2)) = 1.59x10^-24J

Thus, the number of photons required are 84000/(1.59x10^-24)

= 5.2830x10^28.

Hope the explanation is sufficient.