A250.0 gram block is placed on a balance. the balance measures the mass of the block as 243.9 grams. what is the percent error of the block

Idon't really understand this can you me and show your work.☺☺[ chemistry b] subject [ electron transfer in lonic bonds]grade( 12)

Calculate: select the worksheet tab. this tab you calculate the analyte concentration.  fill in the first set of boxes ("moles h2so4" and "moles naoh") based on the coefficients in the balanced equation. (if there is no coefficient, the value is 1.)  record the appropriate volumes in the "ml naoh" and "ml h2so4" boxes.  record the concentration of the titrant in the m naoh box. click calculate. what is the concentration listed

The blackbody curve for a star name zeta is shown below. what is the peak wavelength for this star ?