Object a is postiively charged. object a and object b attract. object b and object c attract. object c and object d repel. what type of charge does object b, object c, and object d possess?

Objects with opposite chargers will attract each other, and objects with the same chargers will repel.  Therefore:

If A is positive, B is negative (they attract)

If B is negative, C is positive (they attract)

If C is positive, D is positive (they repel)!

Hope this helps!!

what was the acceleration of the 2 kg cart?

⇒ 16.0 cm/s2

what was the acceleration of the 4 kg cart?

⇒ 8.1 cm/s2

what was the acceleration of the 6 kg cart?

⇒ 5.3 cm/s2