Answer:
f1 = 12.90 Hz
Explanation:
To calculate the first harmonic frequency you use the following formula for n = 1:

( 1 )
It is necessary that the unist are in meters, then you have:
L: length of the string = 60cm = 0.6m
M: mass of the string = 0.05kg
T: tension on the string = 20 N
you replace the values of L, M and T in the expression (1) for getting f1:

Hence, the first harmonic has a frequency of 12.90 Hz
Answer: True
Explanation:
A force must be applied to set a stationary object in motion.
Answer:
Mass = 1133.33 kg (Approx.)
Explanation:
Given:
Momentum = 2.04 x 10⁴ kg[m/s]
Velocity = 18 m/s
Find:
Mass
Computation:
Mass = Momentum / Velocity
Mass = [2.04 x 10⁴] / 18
Mass = 1133.33 kg (Approx.)
Laurentia, also called the North American Craton, is a huge continental craton. It<span> forms the ancient </span>geological<span> core of the </span>continent of North America.<span> It is made up of present day North America and Greenland. About 300 million years ago, it collided with the southern hemispheric continent of </span>Gondwana<span> and formed the supercontinent called Pangaea.</span><span> </span>