Pengaruh Effective Tax Rate dan Cost of Capital terhadap Investasi pada Aset Tetap: Studi Empiris pada Perusahaan Kompas100 Periode Sebelum dan Sesudah Penurunan Tarif PPh Badan = The Effect of the Effective Tax Rate and Cost of Capital on Fixed-Asset Investment: An Empirical Study of Kompas100 Companies Before and After the Corporate Income-Tax Cut