Answer:
A. animals do not make their own food.
Explanation:
Answer:- C. Hafnium.
Solution:- Mass of the sample is 46.0 g and it's volume is
.
From mass and volume, we can calculate it's density using the formula:



On the basis of the density, this substance could either be mercury or hafnium. Since the substance is a solid at room temperature where as mercury is liquid. So, it can't be mercury.
The right choice is C) Hafnium.
Answer:
Initial temperature, T1 = 99.4 Kelvin
Explanation:
<u>Given the following data;</u>
- Initial volume, V1 = 65.8 Litres
- Final temperature, T2 = 200 Kelvin
- Final volume, V2 = 132.4 Litres
To find the initial temperature (T1), we would use Charles' law;
Charles states that when the pressure of an ideal gas is kept constant, the volume of the gas is directly proportional to the absolute temperature of the gas.
Mathematically, Charles' law is given by the formula;


Making T1 as the subject formula, we have;

Substituting the values into the formula, we have;


<em>Initial temperature, T1 = 99.4 Kelvin</em>
We will assume that the wave is moving in free space, thus, the velocity of the wave would be equal to the speed of light = 3 * 10^8 meters/sec
The velocity of the wave can be calculated using the following rule:
velocity = frequency * wavelength where:
velocity = 3 * 10^8 m/sec
frequency = 2500 Hz
wavelength is the unknown that we want to calculate.
Substitute with the givens in the above equation to get the wavelength as follows:
3 * 10^8 = 2500*wavelength
wavelength = 120 * 10^3 meters