Energy can be one answer! There are many, but energy is a main one.

**Answer:**

F₂= 210 pounds

**Explanation:**

**Conceptual analysis**

**Hooke's law**

Hooke's law establishes that the elongation (x) of a spring is directly proportional to the magnitude of force (F) applied to it, provided that said spring is not permanently deformed:

F= K*x **Formula (1)**

Where;

**F** is the magnitude of the force applied to the spring in Newtons (Pounds)

**K** is the elastic spring constant, which relates force and elongation. The higher its value, the more work it will cost to stretch the spring. (Pounds/inch)

**x** the elongation of the spring (inch)

**Data**

**The data given is incorrect because if we apply them the answer would be illogical.
**

**The correct data are as follows:**

F₁ =80 pounds

x₁= 8 inches

x₂= 21 inches

**Problem development**

We replace data in formula 1 to calculate K :

F₁= K*x₁

K=( F₁) / (x₁)

K=( 80) / (8) = 10 pounds/ inche

We apply The formula 1 to calculate F₂

F₂= K*x₂

F₂= (10)*(21)

F₂= 210 pounds

**Answer:**

**Explanation:**

Stefan's formula for emission of radiation is

E = e σ A ( T⁴ - T₀⁴ )

E is energy radiated , e is emissivity , σ is stefan's constant , T is temperature of object and T₀ is temperature of surrounding. A is area of surface .

E = .35 x 5.67 x 10⁻⁸ ( 298⁴ - 268⁴ ) x 4π x .25²

= 1.9845 x 10⁻⁸ ( 78.86 - 51.58 ) x 10⁸ x .0625

= 3.38 J /s

**Answer:**

A

**Explanation:**

A. The molecules that make up olive oil are longer than those that

make up alcohol, so they have more resistance to sliding past one

another.

Olive oils are unsaturated fats with many carbons whereas, alcohols are typically short with very few carbons.

<span>141.6 million mi,and idk what u mean by how</span>