What Is the Effect of Joint Actions in the Propulsive

question 19

Multiple Choice

What is the effect of joint actions in the propulsive phase of the long jump?
1) action at the ankle moves lower leg backward for balance
2) action at metatarsal-phalangeal joints lifts body upward
3) hip action helps keep trunk in alignment
4) knee action causes thigh to move forward and upward

• A) 1, 4
• B) 1, 2, 3
• C) 2, 3, 4
• D) 1, 2, 3, 4

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Definitions:

Closed System

A physical or economic system that does not interact with or exchange matter with its surroundings.

Say's Law

An economic theory that suggests that supply creates its own demand, meaning that production inherently generates a demand for the goods produced.

Open Economy

An economy linked to the rest of the world through international trade.

Equilibrium GDP

The level of GDP at which total demand for goods and services equals total supply in an economy, indicating a state of economic balance.