How many moles are in 48.4gCu2CO3?

What does the process of natural selection involve

After watching the video "zinc strip in copper nitrate solution", and reading the instructions, click on the link labeled "start" just below the drawing of the pencil tip. follow the direction to complete the 3x3 grid. answer the below questions for the portion of the activity in which sn(s) is placed in agno3(aq)

The chart shows the bid provided by four contractors to complete a job. which contractor is the most cost-effective?