Why must you repeat steps three and four in the scientific method

HNO3 (aq) + H20 (1) ► NO3 - (aq) + H30 + (aq) es Which substance in the reaction is considered to be the acid? HNO3 H2O NO3 H30

Suppose an object is being moved 10 Newtons to the right. At the same time, it is being moved 18 Newton to the left. Calculate the net force of the object. Think about the unbalanced force. Explain how it will change the object's speed and direction.

Which two particles are found in the center of an atom? Reactis electrons and ions protons and neutrons protons and electrons electrons and neutrons

What type of wave is made by earth quakes

A little boy sitting on the floor tosses a ball in such a way that it reaches the level of a tabletop several meters away, moving horizontally, and rolls across the tabletop at constant speed if friction with the air and the tabletop can be ignored,

A constant force is exerted for a short distance on a block of mass that is initially at rest on a horizontal frictionless plane. This force gives the block a certain final speed v.

A football quarterback is moving straight backward at a speed of 3.00 m/s when he throws a pass to a player 20.0 m straight downfield. (a) if the ball is thrown at an angle of 25.

Simone is walking her dog on a leash. The dog is pulling with force of 34 N to the right and simone is pulling backward with a force of 16 N

An object moves with velocity v (t) = t^2-8t+7 a) write a polynomial expression for the position of the particle at any time t greater or equal to zero.

Is a lack of thorns a mutation? (on a plant)