Answer
given,
position of particle
x(t)= A t + B t²
A = -3.5 m/s
B = 3.9 m/s²
t = 3 s
a) x(t)= -3.5 t + 3.9 t²
velocity of the particle is equal to the differentiation of position w.r.t. time.

------(1)
velocity of the particle at t = 3 s
v = -3.5 + 7.8 x 3
v = 19.9 m/s
b) velocity of the particle at origin
time at which particle is at origin
x(t)= -3.5 t + 3.9 t²
0 = t (-3.5 + 3.9 t )
t = 0, 
t = 0 , 0.897 s
speed of the particle at t = 0.897 s
from equation (1)
v = -3.9 + 7.8 t
v = -3.9 + 7.8 x 0.897
v = 3.1 m/s
Answer:
The frequencies are 
Explanation:
From the question we are told that
The speed of the wave is 
The length of vibrating clothesline is 
Generally the fundamental frequency is mathematically represented as

=> 
=> 
Now this other frequencies of vibration experience by the clotheslines are know as harmonics and they are obtained by integer multiple of the fundamental frequency
So
The frequencies are mathematically represented as

=> 
Where n = 1, 2, 3 ....
<span>Of the following gasses, CH4 will have the greatest rate of effusion at a given temperature.</span>
Here are some popular applications of
non-visible electromagnetic radiation:
-- listen to the weather and music on the radio
-- watch a football game on TV
-- change the TV channel from the couch, using the 'remote'
-- make toast
-- warm leftover meatloaf in the "microwave"
-- make a call with your cellphone
-- text a friend with your 'smartphone'
-- surf the internet in your house without wires (with WiFi in the house)
-- use GPS in the car
-- get a new set of dental X-rays made
-- spend 30 minutes in a tanning bed
-- look at your friend's face