1. Suppose \"learning\" is not observable, but is perfectly measurable by a variable that is observable: \"class attendance". What can the instructor do to incentivise learning? (a) Realistically, \"learning'7 is not observable, but \"class attendance\" (While being observable) isn't a very good measure of \"learning\". Name one behavior that 1) is rewarded by incentivising attendance and 2) the principal does not care about. (b) Name one behavior that contributes to \"learning\" that is not \"captured\" by a performance measure linked to attendance. (c) We assumed that giving out marks is somehow \"costly\" for the instructor. Explain how the analysis in ac changes if it is not