Answer:
Left amount of Polonium-210 after 115 days will be 4.5927 microgram
Explanation:
We have given initial mass of Polonium-210 
Decay rate x= 0.502% = 0.00502
Time t = 115 days
We have to find the left amount of Polonium -210 after 115 days
We know that left amount is given by

So left amount of Polonium-210 after 115 days will be 4.5927 microgram
These are the answers for questions 1-7 I wasn’t sure in 8 though
Magnetic force - B.
Electrical force - A.
Gravitational force - D.
Contact force - C.
<h3><u>Explanation:</u></h3>
When a charge moves about its path, it produces a magnetic force around it. This magnetic field is perpendicular to the axis of movement of the charge and is directly proportional to the amount of charge, speed of the charge, and inversely proportional to distance between the charge and the point of measurement. Michael Faraday discovered this phenomenon.
Electrical force of attraction or repulsion is seen between the two charged bodies, or one charged body and one uncharged body which can induce charge to the uncharged body. The attraction or repulsion between the charged bodies are seen if the bodies are close enough, and this is called electrical force.
The gravitational force is also a non contact force that is seen between two bodies which is always attractive in nature and is seen between any two bodies.
A contact force like friction is a type of force that takes place only when two bodies are in contact with each other.
The nurse can follow
these following tips:
For temporary relief
of dryness of mouth from antihistamines:
1. the patient can
chew on sugarless gums
2. the nurse can let
the patient have bits of ice melt in their mouth
3. or the nurse can
give a saliva substitute
If dryness of mouth
does not go away after 2 weeks, seek doctor’s help.
Answer:
The first attempts at domestication of animals and plants apparently were made in the Old World during the Mesolithic Period. Dogs were first domesticated in Central Asia by at least 15,000 years ago by people who engaged in hunting and gathering wild edible plants
Explanation: