While attempting to determine the density of a solid by water-displacement, a student places the solid in a graduated cylinder that is partially filled with water. (The initial volume of water is accurately recorded). The solid, however, is not fully submerged. Nonetheless, the student simply records the final volume of the water as is. How does the carelessness of this student affect the calculation of density? (Assume the mass is accurately determined). Will the calculated density be greater than or less than the true value? Or will the result be unaffected and equal to the true value? Carefully explain.

while cooking a piece of 1/2 pound beef steak, a cast iron pan (2.4kg in weight) was heated 260 celsius.

i think it's c. if you look search electronic symbol on google and then click on wiki it shows you a

a corroding iron, if that's one of your choices

hydrocarbons are organic compounds that contain only hydrogens and carbons. they can be saturated (those which contain only carbon-carbon single bonds) or unsaturated (those which contain carbon-carbon double or triple bonds) in nature. hydrocarbons can undergo several reactions like substitution, elimination etc.  

on substituting one or more hydrogen atoms in hydrocarbon it results in the formation of haloalkane. as the halogen atoms are large compared to the carbon and hydrogen atoms, due to which the molecular weight increases and the bond become polar because of presence electronegative halogen atom and results in the increase in boiling point of the haloalkane.

thus, the correct option is (b) that is the boiling point of the new compound increases on substituting a hydrogen atom with a halogen in a hydrocarbon.