As the pendulum approaches or recedes from which position(s) is the acceleration vector a⃗ a→a_vec almost parallel (or antiparallel) to the velocity vector v⃗ v→v_vec?

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The radiation of the fire causes the saucepan to heat up. the conduction of the saucepan then to distribute the heat over the saucepan and to give heat to the water. the convection of the water distributing the heat within the water, till all the water is boiling

True will be your answer dude