Answer:
B. 1 m/s
Explanation:
Metric unit conversions:
0.3 km = 300m
5 minutes = 5*60 = 300 seconds
So if a seal can reach a depth of 300m in a time of 300 seconds, its diving speed is the distance divided by time duration
v = s/t = 300/300 = 1m/s
So B is the correct answer
Answer:
d = 1.07 mile
Explanation:
The rationale for this method is that the speed of light is much greater than the speed of sound, the definition of speed in uniform motion is
v = d / t
d = v t
the speed of sound is worth
v = 343 m / s
Therefore, the speed of sound must be multiplied by time to do this, all the units must be in the same system, as the distance in miles is requested
v = 343 m/s (1mile/1609 m) (3600s/1 h) = 343 (2.24) = 767.4 mile/h
v = 343 m / s (1 mile / 1609 m) = 0.213, mile/ s
If the measured time is t = 5s we multiply it by the speed
we substitute
d = 0.213 5
d = 1.07 mile
If you want to calculate the speed, this method in general is not widely used, since you must know the distance where the lightning occurred, which is relatively complicated.
Answer:

Explanation:
V = Voltage = 230 V
I = Current = 1.8 A
= Temperature change = 
t = Time taken = 2 minutes
m = Mass of liquid = 750 g
c = Specific heat capacity of the liquid
Energy required to heat the water is equal to the heat released due to current passing

The specific heat capacity of the liquid is 
2/1 i think because if you start with the example of 4 then from air to water makes it 3 and then to glass makes it 2. Therefore you decrease from 4 to 2 which breaks down in the ratio 2:1