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2 years ago

Which years had the least sunspot activity?

Physics

1 answer:

Nostrana [21]2 years ago

3 0

The period between about 1650 and 1700 is when astronomers saw virtually no sunspot activity.

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Which receptors are responsible for the production of saliva (A) auditory receptors (B) optic receptors (C) skin receptors (D) t

Fudgin [204]

Answer:

$\large \boxed{\sf D. \ taste \ receptors}$

Explanation:

When activated, the receptor most likely prompting the production of saliva is the taste receptor. When food enters the mouth, the salivary glands produce the saliva upon the sensation of taste.

8 0

2 years ago

Two charged objects separated by some distance attract each other. If the charges on both objects are doubled with no change in

beks73 [17]

Answer:

a. the force between them quadruples

Explanation:

The electrostatic force between two charges is given by

$F=k\frac{q_1 q_2}{r^2}$

where

k is the Coulomb's constant

q1 and q2 are the two charges

r is the separation between the two charges

In this problem, the charges on both objects are doubled, so

$q_1' = 2q_1\\q_2' = 2q_2$

While the distance does not change, so the new force will be

$F'= k \frac{(2q_1)(2q_2)}{r^2}=4 (k\frac{q_1 q_2}{r^2})=4 F$

so, the force will quadruple.

4 0

2 years ago

What are three mechanisms for reproductive isolation? Which Mechanism isolates two populations of similar frogs with different m

saul85 [17]

The mechanisms of reproductive isolation are:
1) Habitat isolation
2) Behavioral isolation
3) Mechanical isolation
4) Gametic isolation
The isolation happening here is behavioral isolation, because their different behavior patterns prevent the frogs from breeding.

4 0

2 years ago

What is the density of concrete in kilogram per cubic meter.

gulaghasi [49]

Answer:

2400 kilogram per cubic meter

Explanation:

the density of concrete is a measure of its unit weight.

concrete is a mixture of cement, fine and coarse aggregates, water and sometimes some supplementary materials like fly ash, and various admixtures.

5 0

2 years ago

Read 2 more answers

What is the mass of 2.5 mol of Ca, which has a molar mass of 40 g/mol?

ipn [44]

Answer:100 g of ca

Explanation:

4 0

2 years ago