General Motors on Thursday slashed its full-year forecast as its CEO Mary Barra warned of “a current tariff exposure of $4 billion [to]$5 billion.”The company, which owns brands including Chevrolet, Buick and Cadillac, now expects a profit between $8.2 billion and$10.1 billion, down from previous projections of between $11.2 billion and$12.5 billion, as it faces a steep 25% tariff on foreign vehicle imports.It expects adjusted earnings of $8.25 to$10 a share, down from its previous forecast of $11 to$1 ...