In what decade was photography invented? the 1800s the 1820s the 1840s the 1860s

Technician a says that if a valve is open when a piston rises to the very top of a cylinder, the piston may actually strike the valve head and cause serious engine damage. technician b says if the camshaft is located in the engine block, then the engine is called an overhead valve engine, ohv engine, or an in-block camshaft. who is right? a. b only b. both a and b c. a only d. neither a nor b

Meenu wants to create a high quality drawing in a variety of colours. which device should she use for the same?

Who is the first president to use social media as part of his campaign strategy